Cable strap forming apparatus



Dec. 10, 1957 J. R. BUCHANAN 2,815,792

CABLE STRAP FORMING APPARATUS Fil ed Aug. 30, 1954 v INVENTOR/ James E.5616/70/70 CABLE STRAP FORMING APPARATUS James R. Buchanan, South SanFrancisco, Calif.

Application August 30, 1954, Serial No. 453,167

Claims. (Cl. 153-32) (Granted under Title 35, U. S. Code (1952), see.266) This invention may be manufactured and used by or for theGovernment of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

This invention relates to forming dies and more particularly to dies forforming attaching straps capable of supporting multiple rows of cablesor the like.

It is recognized practice to secure cables or pipes to a support byemploying attaching straps that provide for an orderly cable arrangementand, in the case of moving vehicles, prevent cable vibration andaccompanying noises. No difficulty has been experienced in bendingattaching straps to accommodate a single row of cables to be supported;however, in forming straps to accommodate two rows of cables in nestedrelation, the problem has arisen of detachably securing the dies in thesecond row in selected relation to the first row to permit bending thestrap material. At the present time the second row of dies is manuallyheld on the first row, which procedure requires additional personnel,presents a safety problem, and limits the manufacture to a handoperation.

Accordingly, a principal object of this invention is to provide a doublerow die set capable of being interlocked in a strap forming position.

Another object is to provide releasable interlocking means that willpermit the use of interchangeable dies.

Still another object is to provide an interlocked die set capable ofbeing used in a conventional hydraulic, pneumatic or manual press.

Further objects are to provide a die set that will expedite and reducethe cost of manufacturing double row attach straps, and to provide a dieset for forming various strap sizes and shapes capable of tightlyembracing the cables to be supported.

These and other objects will become apparent from the accompanyingdrawing and detailed description.

According to the invention, the foregoing objects are achieved by astrap bending apparatus including two rows of interchangeable diemembers, each die member having a working surface corresponding to thecontour of elongate members, such as a cable or pipe, to be accommodatedby the strap. The dies can be detachably interlocked in various nestedcombinations in a manner to duplicate the over-all configuration of thedesired cable arrangement.

In a specific embodiment, the readily detachable means for interlockingthe two rows of die members comprises the provision of opposedlongitudinal recesses in the adjacent flat die walls in one row, saidrecesses adapted to receive and clamp one or more depending extensionson each of the die members of the second row when the die members of thefirst row are secured together. The depending extensions may bepivotably anchored to their respective die members to permit these diesto be secured on the first die row in a position tilted from thelongitudinal axis of the extension as may occur when the two adjacentdies of the first row between which the second row die rests, have adifferent radius of curvature.

Patent ture; Fig. 2, a diagrammatic side elevation of an assembled dieset on which is being formed the attaching strap; and Fig. 3 an explodedperspective view, partially in section, of the die set shown in Fig. 2.

Referring to Fig. l of the drawing, an attaching strap 2 formed by thedie set of this invention is shown securing a double row of cables 4- orany other elongate members such as pipes, wires, etc. to a supportingstructure 6. The upper row of cables is normally nested with the lowerrow, strap 2 being constructed to conform to the combined configurationof the cables to insure a snug fit and prevent lateral movement betweenthe cables, strap and supporting structure that may cause vibration,noise, and cable breakdown.

The die set in Figs. 2 and 3 is generally indicated by reference numeral8 and comprises a first row It? including two or more die members 1011to 10d, and a second row 12 including one or more die members 12a and12b adapted to be nested with the first die members. The working surfaceon each die member has a configuration corresponding to the cable to beaccommodated by the strap, which in the illustrated embodiment aresubstantially cylindrical. Both rows of die members are interchangeableand a sufiicient stock of different size dies is maintained to provideas many combinations as are necessary to duplicate the desired cablearrangement.

The dies in first row 10 are provided with rectangular bases 13 adaptedto be supported on a tray 14 in any suitable manual or power-operatedpress, not shown, and fixed thereon by a clamp 16 which compresses thedies in the selected assembly. As will be presently described, clamp 16also functions to secure the die members in second row 12 in theirnested position on the first row. The dies in both first and second rowsare interlocked by means which comprise one or more longitudinalrecesses 18 constructed preferably in the opposing fiat die walls 20 oflateral die members 10a to 1011 in the first row.

Each pair of opposing recesses 18 cooperate to form a force in formingthe strap. The cross-sectional shape of recesses 18 and pin 22 may vary,although a circular shape is preferred because it offers the maximumbearing surface and is simple in construction. Although recesses 18 maybe constructed in only one die wall of adjacent dies it is preferred toprovide recesses in both opposing walls to insure uniformity in dieswhich are interchangeable.

When working surfaces are round as shown and adjacent dies havedifferent radii, it is necessary to permit second row die members 12aand 12b to move relative to their pins 22 so that the die members can besecurely seated on both adjacent working surfaces of the lower diemembers. Die members 12a and 1212 are completely round in cross-sectionto provide a two point contact with the lower adjacent surfaces and,also, because the effective working or strap-forming surfaces of diemembers 12 will vary in circumference depending on the radii of thelower adjacent working surfaces.

bers and their anchoring pins 22 is accomplished by forming the upperend of each pin with an eye portion 24 through which is freely passed ashaft 26 secured in the ends of the die members. The central portion ofeach die member is slotted at 28 to permit the member to Patented Dec.10, 19 57 7 The width of the die mem- Referring to Fig. 2, relativemovement between the upper die mem-v move freely to either side of thepins to a position determined by the adjacent die.

Operation of the die set is described with reference to Fig. 2 whereinthe first and second rows of die members have been assembled in apredetermined relation according to the selected arrangement of cables 4to be accommodated, as shown in Fig. 1. Both rows of die members aresecured by clamp 16 on tray 14 which is mounted in the press. It shouldbe noted the lateral walls of the lower die members are in abuttingrelation to insure uniformity between the formed strap and cablearrangement. A blank of strap material 30 is positioned over the nesteddies, one end of the strap material being secured by a press member 32and the remaining strap material successively held and bent over eachdie working surface by a holding press member 34 and a bending pressmember 36, and the opposite end finally being formed by a press 38.Obviously, other press arrangements can be used which will bend thestrap material at one time or, conversely, the strap may be manuallyformed by hammer and chisel.

By use of the foregoing invention, multiple row attaching straps can beformed manually or by any suitable press in a safe and expeditiousmanner. This result is achieved by providing an interlocking means thatprevents accidental separation of the dies during the strap formingoperation. The interlocking means is operated automatically as the diesare clamped in their assembled relation and enables all die members tobe interlocked in the same manner so that they can be interchangeable.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is, therefore, tobe understood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

I claim:

1. Apparatus for forming supporting straps for nested upper and lowercable-like members, said apparatus including a bottom row ofinterchangeable independent die members adapted in height and surfacecurvature for forming when adjacently disposed an upper surfaceconforming in over-all curvature with the upper surface of said lowernest-forming cable-like members, an upper die member conformed in sizeand curvature with an upper cable-like member, and means for holdingsaidupper die member firmly in a nested position on said adjacently-disposedlower die members, said means including an arm pivotally carried by saidupper die member and adapted to extend through the meeting surfaces ofsaid adjacently-disposed bottom row die members, said meeting surfacesbeing recessed for closely receiving said arm and maintaining saidnested relation.

2. Apparatus for forming supporting straps for nested.

upper and lower cable-like members, said apparatus including a bottomrow of interchangeable independent die members adapted in height andsurface curvature for forming when adjacently disposed an over-all uppersurface conforming in curvature with the upper surface ofsaid lowernest-forming cable-like members, an upper.

die memberconformed in'size' and curvature withan upper cable-likemember, means for holding saidupper die member firmly in a nestedposition on said adjacentlydisposed "lower 'die members, 'said' means"including an armpivotally carried by said upper-die member and adaptedto extend through the meeting surfaces of-said adjacently-disposedbottom row diemembers, saidrneeting surfaces being recessed for closelyreceiving said arm, andmeans for pressing together saidbottom row of diemembers whereby "saidbottom members securely grip 'said' arm maintainingsaid nested relationship.

3. Apparatus'for forming supporting straps for nested upper and'lowercable-like members, said" apparatus 'including a bottom row ofinterchangeable independent die members adapted in height and surfacecurvature for forming when adjacently disposed an over-all upper surfaceconforming in curvature with the upper surface of said lowernest-forming cable-like members, an upper die member conformed in sizeand curvature with an upper cable-like member, and means for holdingsaid upper die member firmly in a nested position on said adjacentlydisposed lower die members, said means including an' arm pivotallycarried by said upper die member and adapted to extend through themeeting surfaces of said adjacently-disposed bottom row die members,said meeting surfaces being recessed for closely receiving said arm andmaintaining said nested relation, and said arm having its pivotal axissufiiciently displaced radially from the central axis of said upper diemember for permitting said arm to align itself with said recess undervarying nested dispositions.

4. Apparatus for forming supporting straps for nested upper and lowercable-like members, said apparatus including a bottom row ofinterchangeable independent die members adapted in height and uppersurface curvature for forming when adjacently disposed an overall uppersurface conforming in curvature with the upper surface of said lowernest-forming cable-like members, an upper die member conformed in sizeand curvature with an upper cable-like member, means for holding saidupper die member firmly in a nested position on said adjacentlydisposedlower die members, said means including an arm pivotally carried by saidupper die member and adapted to extend through the meeting surfaces ofsaid adjacentlydisposed bottom row die members, said meeting surfacesbeing recessed for closely receiving said arm, and means forpressingtogether said bottom row of die members whereby said bottommembers securely grip said arm for maintaining said nested'relationship,said lower die members having flat-surfaced bottom and side walls andsaid pressing means acting upon said side Walls, whereby said walls ofsaid lower die members are presed into flush contact.

5. Apparatus for forming supporting straps for nested upper and lowercable-like members, said apparatus including a bottom row ofinterchangeable independent die members adapted in height and uppersurface curvature for forming when adjacently disposed an over-all uppersurface conforming in curvature with the upper surface of said lowernest-forming cable-like members, an upper die member conformed in sizeand curvature with an upper cable-like member, means for holding saidupper die member firmly in a nested position on said adjacentlydisposedlower die members, said means including an arm pivotally carried by saidupper die member and adapted to extend through the meeting surfaces ofsaid adjacentlydisposed bottom row die members, said meeting surfacesbeing recessedfor closely receiving said arm, and means for pressingtogether said bottom row of die members whereby said bottom memberssecurely grip said arm for maintaining said nested relationship, saidlower die members having flat-surfaced bottom and side walls and saidpressing means acting upon said side walls whereby said walls of saidlower die members are pressed into flush contact, the height of saidwalls being fixed in accordance with the upper surface curvature of eachlower die member.

References Cited in the file of this patent UNITED STATES PATENTS

